Pneumatic impact-tool.



PATENTED JULY 14, 1908.

- G. L. BADGBR.-

PNEUMATIG IMPACT TOOL. APPLICATION FILED JAN. 8, 1906.

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` accompanying drawings.

GEORGE L. BADGER, OF QUINCY, MASSACHUSETTS. u

PNEUMATIC IMPAC'EfTOOL.

Specification ofv Letters Patent. A

Patented July 14,1908'i Application filed'January 8, 1906. Serial N0. 295,083;

To all 'whom it may concern.' Be it. known that I, GEORGEL. BADGER, a citizen of. the United States, residing at Quincy, in the county of Norfolk, State of Massachusetts, have invented a certainnew and useful Improvement in Pneumatic Imact-Tools, of which the following is aspeciation, reference being had therein to the This invention relates to improvements in neumatlc 1m 'act-tools, and more 'particuarly to that c ass in which it is essential to rotate the working-tool with relation 'to the work as when drilling holes in stone.

yThe princi alobjects of the invention are to provide urable and cheaplyconstructed means to hold the working-tool in alinement with the piston,'to limit the rearward movement of the workin tool, to rotate the same, and to permit a ongitudinal movement of the working-tool with relation to the cylinder when' the `working-tool lis rotated.

Inpneumatic impact-tools of the Atype in which the iston strikes directly .on the workingetool) in order to obtain the best ref sults, it is necessary that the working-tool shall be, in its proper-longitudinal position withk relation to the cylinder at the moment of im act. roun shank on the end o the working-tool which lits a hole inthe -end of the cylinder,` the shank being smaller tha-n the body of the working-tool, thus forming a shoulder which serves to limit its rearward movement.` This is objectionable because of the expense of forming and malntalnmg the round Shanks of tl1e'working-tools all of uniform diameter and length, as they should, be to obtain the best tools do not fit properly., and the wear of the shoulder on the steels and the end ofthe hole causes longitudinal displacement of the steel. Insome tools of this type a bushing or socket is employed having a bore of two diameters, the'smaller bore being at the rear, thereby forming a shoulder against which-the end of the working-tord bears to limit the rearward nmvement. Tl Le end of the piston is made It is the usual ractice toform abushing.

i small enough .to pass through the small bore of the bushing and strike the-end'ofthe working-tool. This construction is suitable for light work, such as lettering and. carving, but

lor'heavy work, the end Vof the iston 1s too small and breaks when the stan ard sizesof p steel are employed.

In my application Serial No. 244,765, filed February 8, 1905,v I haveshown a striker or block interposed between the working-tool and the iston adapted to receive and transmit the low of the piston and to limit the rearward movement of the working-tool. This construction allows for the employment of standard steels4 without any reforming for the shanks whatever. On account of the variation in the sizes of thesteels, the chuck cannot be made to fit the steels closely, and asK it `wears larger in use, it is difficult to maintain the working-tool in alinement with the piston. Thisis also the case when a round shank and shoulder are used, as the hole for the shank wears and becomes too large, and when the working-tool is not in alinement with the piston, the piston does not strike the end of the working-tool squarely,v thus lessening the force of the blow and tending to drive the working-tool to one side and bind the same in the hole of the cylinder or I have found that in some cases better results are obtained when the piston strikes theworking-tool directly, and by providing means for holding the rear end of the worky ing-tool in alinement with the piston, and also limiting its rearward movement independently of the hole in the bushing' or socket, the objectionable features a ove mentioned are practically overcome,

The ends or heads of the working-tools are litted to the holder at a veryv slight expense, the heads being of practically the same form used for hand drilling; there is no waste in using the steels for other purposes;

the steels being of full size and without shoulders, there is no breakage of Shanks', a close t in the socket is not required, and the wear of the hole doesnot interfere with the proper operation of the tool, as the pist0n always strike squarely onthe end of the steel; the bearing surfaces limiting the rear? ward movement are so large that the wear is veryslight and allthe 'sl eels used are always maintained .atl the proper `distance for the piston to strike 'the mosteffective blow. When tools .otthis class are emplo.yed for heavy work, it is essential in order to obtain the best results that the working-tool shall be free to move longitudinally with relation to the cylinder in order that the cylinder -may be -returned to or maintained in the proper position after the working-tool is struck by the piston, as on account of the vibration of the tool there is a tendency for the cylinder to move rearward or away frere the working-tool.

There is always a tendency for the work-- ing-tool to bind in the hole being drilled, es

pecially when using single or ilat bits, and when the workin -tool is rotated by means of a socket r ciuck adapted to engage a non-circular shank thereon, the friction is .be hereinafter described and pointed" out'in or chuck in position.

the claims. n

In the accompanying drawings,-Figure 1 is an elevation partly in section of a tool embodying my invention, showing the lower Aportion broken away. Fig. 2 is a modification showing other means to hold'the socket Fig. 3 is a modifica- )tion showing the stop for the working-tool Referring to the drawings,the cylinder integral with the socket.

is denoted by'l.

2 is the forward end of the piston', 3 is the socket or chuck and 4 isy a stop-ring. A bushing 5 is adapted to retain the stop-ring and socket in assembled position in the cylinder. A'handle 6 is secured to the socket bymeans of which the latter is rotated to roe. tate the workingftool 7.

-In the mo cation shown in Fig. 2, a spring-cli 8 isadapted to retain the socket in the cy inder. l I have not deemed it necessary to show and describe in detail the construction lof the c linder, valve and piston, as the construction ofthe samevdoes not form an essential partof the' presentinvention which is equally applicable to the pneumatic tool shown in "my application hereinabove" referred to or ot er types of neumatic tools.

The shank o y the working-tool 7 is of noncircular cross-section except at the rear end which is of circular cross-section and tapered to fit the tapered hole in the stop-ring 4 so that it will project through the latter a 'short distance as shown. The stop-ring is made a workin fit in thecounterbore oi the cylinder, an its rearward ina-vement is limited by the shoulder 9. In the construction shown in Fig. 1, the socket 3 is provided with a flange which fits the counterbore of the cylinder loosely, and the smaller diameter is a working lit in the bore of the bushing 5. 70.

The opening through the socket is of noncircular cross-section ada ted to receive the shank of the working-too so that the latter will slide freely therein. The outside diameter of thel bushing 5 is made so that it is a tight driving fit 1n the counterbore of the cylinder.

The distance between the rear end of the bushing 5 and the shoulder 9 of the cylinder is enough greater than the thickness of the stop-rlng and the flange 10 of the socket to allow the stop-ring to move out of the path of the piston and revent the end of the piston I from striking t e stop-ring when the Jorking-tool is not in its proper position, which often occurs when startin holes .in account of the jumping of the too due to the care lessness of the operator.' This permits the lshoulder 12 on the piston to strike the shoulder 13 of.' the cylinder. It will vbe understood that when the tool isused in a vertical position the stop-ring will move away from the shoulder 9 by gravity when the workingtool is removed. i `V In order to accomplish the best results, it 95 is necessary to provide for a considerable range of movement of the stop-ring. The tools used for certain purposes such as drilling strike such a powerful blow that in order to prevent injury to the tool it is necessary to 100 allow considerable space in which the motive y fluid may cushion the blow of thc piston when the working-tool is displaced and as Abefore stated the stop-ring requires a` sufli' cient space to move out of the path of the piston.

As shown in the drawings, when the working-tool is in its 'normal position, there is a space 11 between the stop ring and the socket. The handle 6 is secured to the 110 socket in such vposition as to allow a longitudinal movement of thev latter with relation to the cylinder, so that if the shank of the working-tool binds in the socket when the' working-tool is somewhat forward/of its proper 1'15 osition, the cylinder can move forward by the bushing 5 sliding on the socket 3 to bring the working-tool into proper working osition. This feature is of great importance for portable pneumatic hand tools for drilling holes in rock, as it relieves -the socket and cooperating parts from a great deal of the strain and wear that they wouldotherwise receive. It also allows ythe tool to do more ra id'work'.

- hen thevshank of the' working-tool is. gripped tightly by the socket, as is the case when the cutting-bit binds in the hole, and., the operator tries to turn it-by pressing on the handle, the blow of the piston' on thend 13G i with the rock, fthe cylinder is moyedrearwardly a short dlstance; 1n orderv to return' circle in order to drill a round hole. p necessary 'for the proper working of the tool y of the working-tool tends to carry .fthe-latterforward, but since the other end isin contact the cylinder to the proper relative position, the operator must press -the same forward..

In the drawings the lworking-toolis.,shown in its rearward .seated position. ,.Wlien, however, the cylinder has movedrearward-ly from the working-tool a short distance, Vthe .stop ring will not rcss on the shoulderfQ of the cylinder, and t e cylinder is then free to slide on the socket and be moved forward by the operator to reseat the working-tcol since there is a sulicient range of movement rovided for this purpose between the han le 6A This is easily and the end o the cylinder. done with the construction shown yin the drawings, but Whenzthe shankl of the working-tool must slide in the socket, the operator is not able to exert suflicient pressure to accom lish this result. l

A though a great many devices for rotating the workmg-tool for rock`drills v have been proposed, the severe requirements of portable pneumatic hand or unmounted drills has led to the almost universal adoption of a separate lever 0r wrench which 1s sli pecl over the working-tool and held in one and of .the operator. This separate wrench is verv inconvenient for the operator, and itis desirable that the means for rotating the working-tool be part of the pneumatic drill.

For plug and feather, .work, the working-4 tools are dulled guick'fly and haveto ybe changed often. l hen the rotating means fis held-in place, the operator has the free use of both hands for inserting anothersteel. I prefer theconstruction shown in Fig. 1 where the socket is retained in thecylinder bythe bushing 5, but this is 'not' essential as the socket may be retained in the cylinder by any suit-able means as by the sprin -clip 8 shown in Fig. 2. It is not essentlal ,t at the working-tool be rotated through a complete Itis not that means shall be provided forautomatically retaining the socket within'the cylinder; it is simply a'matter oi convenience for` the operator, as when so retained the rotating means does -not need his 'attention to.

keep it in proper-position.

In operation, the working-toolis held to thework by the operator pressing ae'ainst' the handle at the rear end of the tool with one hand. The working-tool is turnedforward and back through part of a revolution by means of the handle. 6 ,which is grasped by.

the other hand of the operator.

In the modification shown in Fig. 3 instead V'or' the employment of av removable stop ring 4, such as shown in Figs. 1 and 2, the socket 3 is extended rearward to engage the shoulder 9 in the forward end of the cyl- Workingtool to"`limit its rearward movement and .hold itin alinement with the pis- .ton.

inder, adapted to engage the shank of the with a. tapered r lbeing-free to move `out'ol reachgof the [piston inder, and lthe rear portion' of the socket` is formed with tapering sides 4 which serve -as a stop for-the tapering rear end of the workin -tool This construction isvnot so desirab eon some accounts as the use of the movable stopring shown in Figs. 1 and 2, because more vibration is imparted to the socket, but'such construction I should conaider as coming within the scope of my invention.

Vl/'hatVI claim is:

1. In a pneumatic impact-tool, a cylinder andpiston, a working-tool, a socket in which the shank of the working tool slides easily, said shankbein 'free to move out of reach of the' piston when the lworking-tool is not in contact withithe work, and means longitudinally movable with relationto the c linder adapted toy engage the rear. end o' the 2. In a pneumatic impact-tool, a cylinder and piston, a socket atthe forward end of the cylinder adapted to receive the shank of a Working-tool, said working-tool being free to move out of reach of the piston'when not in contact with the work, and means longitudinally movable with-relation'tol the cylland pis-ton, a socket at the forward end of the cylinder adapted to receive the shank lof a Working-tool, said working-tool being freeto move out of reach of the piston when 11o not in contact with the -work, a stopringlof cated rearward of said` socket adapted to limit the rearward move-'meut of theworkingtool, said stop ring being longitudinally mov?. able and adapted to move the rear end of the working-tool in alinement with the piston.

5; In a pneumatic impact-tool, a cylinder v and` piston, a socket at 'fthe forward yend of the cylinder vada t cd to receive theshank of aworkuig-tooY 1wprking-toolA rovided 23 end, said wornng-tool when `not in contact with the work,` and a movable stop-I fing'` adapted to engage the tapered endgQ-.thc Working-tool and hold 1.25 the latter nalinenient :with thepiston.l

6. In a'pneumaticimpact-tool, a cylinder and pistoma Sciclie,tNat the forward end of the cylinderadap` geceivethe shank of a Working-toolfa'w1 'i11gtool provided with 13 .stop-ring adapted to engae AaI tapered rear end, said Working-tool being freeto move `out of reach of the piston when not incontact with the Work, and a movable the tapered end of the working-tool, sai longitudinally movable 1with re ation to the cylinder.

7. In apneumatic impact-tool, a cylinder and piston, a socket at the forward end of Athe cylinder adapted to looselyengage the ing-tool being tapered, means adated to engage thevtapercd end of the working-tool to limit its rearward movement and hold it in alinement with thepiston, said means being free to move out of reach of the piston when the working-tool is not in contact with the work and means whereby the workingtool may beerotated.

9. In a pneumatic impact tool, a cylinder and piston, a socket rotatably mounted with relation to the cylinder and adapted to engage the shank of a working-tool, said socket being longitudinally movable with relation to the cylinder and working-tool, said biking-tool being free to move out of the socket when not in contact with the work, and means hereby the socket may be moved longitudinally and rotated to rotate the working-tool.

10'. In a pneumatic impact-toolfa cylinder and piston, a socket rotatably' mounted with relation to the cylinder and. adapted to engage the shank of a working-tool, means adapted to .engage the rear end of the working-tool to limit itsrearward movement, said means being longitudinally movable with rclation to the cylinder, 'and tree to move out;

,of reach of the piston when the working-tool is not in contact with the work, and means whereby said'socket may be rotated to rotate the working-tool. i

1.1. In a pneumatic impact-tool, a cylinder and piston# a socket rotatably.mounted Vwith relation to the cylinder and adapted to engage the shank of a'working-tool, means i11- dependent of said socket and longitudinally movable with relation thereto adapted to limit the rearward movement of the workingtool and means whereby the socket may be rotated to rotate the working-tool.

2.- Inl a pneumatic 4impact tool', a cylinder -'and piston, a socket adapted to receive the shank of a working-tool, means independent of the piston whereby said socket may be moved foiward and rearward with relation to the cylinder and working-tool, and may be rotated to rotate the working-tool.

' 13. In a pneumatic impact-tool, a cylinder and piston, a socket rotatably mounted with 'relation to the cylinder and adapted to engage the shank of a working-tool, means independent of the piston whereby said socket may be vrotated and may be moved forward and rearward with relation to the cylinder Aand working-tool, and means to retain the (siocket in position with relation to the cylin- 1.4. In a pneumatic impact-tool, a cylinder ing-tool, and means to retain the socket in Aassembled position with relation to the cylinder.

15. A In a pneumatic impact-tool, a cylinder and iston, a socket adapted to receive the shan of a working tool, a working-tool, a stop ring mounted in the cylinder adapted to engage the rear end of the working-tool and limit the rearward movement ot the working-tool and hold it in alinement with the piston, said stop ring and working-tool bcing free to move out ci reach oil' thc piston when not in contact with the work, and a bushing in the forward end ol the cylinder held in fixed relation thereto and adapted to retain said stop ring and socket in the. cylinder. Y

16. In a pneumatic impact tool, a cylinder and piston, a bushing in the forward end of the cylinder held in fixed relation thereto, a socket rotatably and longitudinally movable in the cylinder and retainedtherein by the said bushing and adapted to engage the working-tool, said working-tord being free to move out of reach ci" the piston when not in contact with th(` work, and means whereby said 'socket may be rotated to rotaie the wolking-tool.

17. ln a pneumatic impact tool, a cylinder and pist-on, a socket adapted to receive the shank `ol` a working-tool, meansl to limit the rearward movement of the workingtool, said means being free-to move out of reach of the piston when the*working-tool is not in ,contact withthe work, said s -=cket being lon-- gitudinally movable with relation to the cylinder and working-tool, andhineans whereby the socket may be rotated to rotate the working-tool.

18. In a pneumatic impact-tool, a cylinder and piston, a working-tool receiving `direct piston impact, and free to move out of reach of the piston when not in contact with the lili' work, means at th'e rear end of the workingv A tool to limit its rearward movement, saidl seaaee means being longitudinally movable with relation to the cylinder an the working-tool.

19.' In a pneumatic impact-tool, a cylinder and piston, a working-tool receiving direct 1 piston impact, means torotate the workingtool, and means atthe rear end of the Working-tool to limit its rearward movement, said means being lcngitudinall movable with re lation to the cylinder an the Working-tool.

' 20.Y Ina pneumaticimpact tool, a cylinder and piston, a working tool receiving direct piston im act, and a socket in which the shank of t e working tool is fitted. loosely and is free to move forward with relation to the `socket independent of the position of the and piston, a Working tool receiving direct piston' im act, and a socket in which the shank of t e working tool is fitted loosely and is free to move for-ward with relation to the socket independent of the position of the socket in the cylinder when the working tool is not lin contact withv the work, the working toolA and cylinder both being longitudinally movable with relation to the socket.

22. In a pneumatic impact-tool, a cylinder and piston, a working-tool, an intermediate member between the cylinder and workingtool adapted to limit, the rearward movement of the latter, the working-tool being normally free to move forward out of. reach of thefpistonwhen not in contact with the work, said member being longitudinally movable with relation to thecylinder.

23. In a pneumatic impact-tool, a cylinder and piston, a working-tool, an intermediate member between the cylinder and`workingtool adapted to loosely engage the rear end of the working-tool, the latter being normally free to move forward out of reach of reach of the piston when not in contact with the work and a shoulder on the cylinder which forms a sto for said intermediate member when the atter is in its rearward position.

' 25. In a pneumatic impacttool, a cylinder and piston, a working tool free to move out I of reach of the piston when not in contact Vwith the work, an intermediate member besaid intermediate member beingr longitudinally movable withv relation to the cylinder andfree to rotate with' relation to the working-tool. f

26. In a pneumatic impact-tool, a cylinder andpiston, a Working-tool free to move out vofreach of the piston when not in contact tween the cylinder and working-tool adapted to limit the rearward 'movement of the latter, said intermediate member being longitudinally movable with relation to the cylinder and free to rotate with relation to the working-tool, 4a bushing` in the forward end of the inassembled position. 27. In a pneumatic impact-tool, a cylinder 'of reach of the piston when notv in Contact with the work, a socket longitudinally mov.- able with relation to the cylinder adapted to loosely engage the shank of the working-tool, a bushing in the forward end of the cylinder held in fixed relation thereto, and adapted to retain said socket in assembled positionJ and vmeans rearward of said socket adapted to limtthe rearward movement of the workingtoo 2-8. In a pneumatic impact-tool, acylinder and piston, a Working-tool 'receiving direct piston impact and. free to move out' ci reach of the piston when not in contact with the work, means adapted to engage the roar end movement, said means beingr longitudinally movable with relation to the'working-tool and cylinder;

29. In a pneumatic impact-tool, a cylinder and piston, a working-tool receiving' direct of the piston when not in contact with the work, means adapted to engage the rear end of the working-tool to limit its rearward movement, said means boingr longitudinally and rotatably movable with relation to the cylinder. y i

30. In a pneumatic impact-tool, a cylinrect piston impact and free to move out of reach of the piston when not in contact with the work, a socket adapted to engagethe shank of the working-'tool and limit its rearward movement, said shank being longitudinally movable in the socket, and said socket bein longitudinally movable with relation to t e cylinder.

31. In 'a pneumatic 'impact-tool, a cylin- 'der and piston, a working-tool .receiving and piston, a working-tool fre'e to move out of the working-tool to limit its rearward piston impact and free to move out of reach tween the cylinder and working-tool adapted v,- to' limit the rearward movement ofthe latter,

with the work, an intermediate member becylinder held in fixed relation thereto and adapted to retainl said intermediate member.

movable with relation to the working-tool der and piston, a working-tool'receiving didirect piston impact, a socket and means .adapted to engage the shank of the workingtool and limit its rearward movement, said shank being longitudinally movable iii the socket, said Socket being longitudinally and rotatably mounted with relation to the cylinder and means whereby the socket may be rotated to rotate the working-tool,

32. In a pneumatic impact-tool, a cylinder and piston, a working-tool, -a socket longitudinally movable with relation to the v cylinder and means adapted to loosely engage the shank of the working-tool and limit its rearward movement, said working-tool being normally free to move forward with relation to the socket and means to retain said socket in assembled position with relation to the cylinder. 1

of the cylinder, a working-tool receiving 33. In a pneumatic impact-tool, a cylinder and piston, a socket at the forward end direct piston impact, means adapted to enage the rear end of the Working-tool to 4i mit its rearward movement,I said. means being longitudinally and rotatably movable with relation to the working-tool and cylinder, and free to move out of reachof the piston when the working-tool is not in contact with the work.4

lof the cylinder, a working-tool, means adapted to receive the shank of the workingtool and limit its rearward movement, said means being longitudinally movable with relation to the cylinder and free to move out of reach of the piston when the working-tool is'not in Contact with the work.

In testimony whereof I aiiiX my signature, in presence of two witnesses. j

GEORGE L. BADGER. 'Vitiiesses:

THOMAS F. MCANANEY, y CHARLES H. MCANA'NEY. 

